IMMOBILISATION METHOD OF RADIONUCLIDES OF ALKALINE-EARTH AND RARE-EARTH ELEMENTS IN MINERAL MATRIX

摘要

FIELD: power industry. ^ SUBSTANCE: immobilisation method of radionuclides of alkaline-earth and rare-earth elements in mineral matrix on the basis of reactions of metasomatic substitution in "wet" conditions differs by the fact that it involves the following: passage of nitrate solution of the above radionuclides through the column filled with particles of minerals with sizes of 0.400.63 mm of model granite mixture or natural granite with crystalline water-free sodium orthophosphate, at mass ratio of sodium orthophosphate to the mixture which is equal to 1:34; dehydration of the contents of the column by heating from room temperature to 400C; saturation of the column contents with liquid sodium silicate with silica modulus equal to 2; the next annealing of the obtained mineral composition at temperature of 900-1250C and atmospheric pressure, or hot pressing at temperature of 815-900C and axial pressure of not more than 700 kg/cm2 till crystalline mineral matrix containing the radionuclide phosphate is obtained. ^ EFFECT: invention allows optimising the method that allows reliable fixation of radionuclides in crystalline mineral matrix. ^ 4 cl, 2 dwg, 6 ex